Electrical equipment of various types is subject to a variety of types of malfunctions. Currently with central office telephone equipment there is a considerable time delay before malfunctions are detected. There is a further time delay and considerable effort is expended to locate, identify and correct malfunctions in telephone equipment after it is determined that a malfunction has occurred.
Presently, once it is determined that a malfunction has occurred, the practice is to dispatch a troubleshooter to a particular area without being certain as to the exact location or precise nature of the problem. The apparatus of the present invention overcomes a number of these problems by continuously monitoring the operation of electrical equipment and, when a malfunction occurs, information concerning the type of malfunction and location of the malfunction is transmitted back to a central location from which a repair person can be dispatched to make the repair.
There are no known remote monitoring systems that can monitor SLC 96 telephone equipment alarms other than stand alone microprocessors and these would involve considerable cost.
Pickett U.S. Pat. No. 3,268,867 discloses a system for centrally monitoring a number of remote positions such as telephone systems but this monitors pressure at selected remote points and requires two-wire conductor pairs along the cable and does not employ a resistance network to sense the state of change of different switches.
U.S. Pat. Nos. 3,105,882, 3,105,883, 3,259,892 and 3,444,336 disclose remote monitoring of the pressure conductor in a pressurized cable.